3GPP (3rd Generation Partnership Project) is a project which performs investigation and preparation of a specification of a mobile communication system on the basis of a network where W-CDMA (Wideband-Code Division Multiple Access) and GSM (registered mark) (Global System for Mobile Communications) have been developed. In the 3GPP, the W-CDMA system has been standardized as a third generation cellular mobile communication system, and the services have been started successively. In addition, HSDPA (High-speed Downlink Packet Access) in which a transmission speed has been enhanced further has been also standardized, and the service has been started. In the 3GPP, investigation is promoted with respect to evolution of the third generation radio access technology (hereinafter, also referred to as “LTE (Long Term Evolution)” or “EUTRA (Evolved Universal Terrestrial Radio Access)”) and a mobile communication system to realize a higher-speed data transmission and reception using a wider frequency band (hereinafter, also referred to as “LTE-A (Long Term Evolution-Advanced)” or “Advanced-EUTRA”).
As a communication system in the LTE, an OFDMA (Orthogonal Frequency Division Multiple Access) system and an SC-FDMA (Single Carrier-Frequency Division Multiple Access) system in which user-multiplexing is performed using subcarriers which are mutually orthogonal is investigated. That is, in a downlink, the OFDMA system that is a multi-carrier communication system is proposed, and in an uplink, the SC-FDMA system that is a single-carrier communication system is proposed.
On the other hand, as a communication system in the LTE-A, it is investigated to introduce a Clustered-SC-FDMA system (also referred to as Clustered-Single Carrier-Frequency Division Multiple Access, DFT-S-OFDM with Spectrum Division Control and DFT-precoded OFDM) in addition to the OFDMA system in a downlink and the SC-FDMA system in an uplink. Here, in the LTE and LTE-A, the SC-FDMA system and Clustered-SC-FDMA system proposed as an uplink communication system have a characteristic feature that PAPR at the time of transmitting data (information) (Peak to Average power Ratio: a ratio of a peak power versus mean power, transmission power) can be suppressed to a low level in terms of the characteristic of the single-carrier communication system (single-carrier characteristic).
In addition, in the LTE-A, it is investigated that a mobile station apparatus transmits a reference signal (hereinafter, also referred to as a sounding reference signal, SRS) to a base station apparatus using an uplink in order for the base station apparatus to measure a channel of the uplink. A base station apparatus carries out scheduling of a mobile station apparatus based on the SRS transmitted from the mobile station apparatus, and for example, performs allocation of physical uplink shared channel (PUSCH)) resources and performs determination or the like of a modulation scheme and coding rate to be applied to the PUSCH.
With respect to transmission of an SRS by a mobile station apparatus, it is investigated that a base station apparatus instructs (request, trigger) a mobile station apparatus to perform transmission of aperiodic SRS (hereinafter, also referred to as A-SRS: Aperiodic SRS, Dynamic SRS, and Scheduled SRS) in addition to transmission of periodic SRS (hereinafter, also referred to as P-SRS: Periodic SRS) (Non-patent document 1, non-patent document 2).